What was found
PILOT REPORTED A LOUD 'BANG' AND IMMEDIATE ROUGH RUNNING ENGINE 10 MILES OUT FROM LANDING. AIRPORT AND LANDING WERE MADE WITHOUT INCIDENT. INSPECTION FOUND NR 5 CYLINDER HEAD HAD SEPARATED FROM CYLINDER BARREL. ANNUAL INSPECTION HAD BEEN COMPLETED 11 HOURS PRIOR AND NR 5 COMPRESSION WAS 72/80 WITH NO EVIDENCE OF CRACKS. ENGINE WAS A TCM FACTORY OVERHAUL WITH 818 HOURS TSMOH. NOTE: AD 86-13-04 DID NOT APPLY.